1. Technical Field
The present disclosure relates to an impedance matching circuit of a communication apparatus, and more specifically, to an impedance matching circuit able to adjust mutual inductance and coupling coefficients, and reduce the occupied size of the circuit.
2. Related Art
Communication systems or sensor systems such as a radar system operate using high-frequency signals. Since the high-frequency signals are not transmitted but reflected when an impedance mismatch exists, they have characteristics of severe attenuation. Therefore, a matching circuit is indispensably required in the communication systems, and a matching circuit may be designed to have a desired impedance value at a specific frequency by using elements such as at least one inductor or at least one capacitor.
As described above, in the communication systems using the high-frequency such as a radio frequency (RF) system, the impedance matching circuit is used to resolve the problem that signals are not transmitted but reflected when an impedance mismatch exists. However, there are many limitations in designing the matching circuit. Specifically, in order to match a large impedance to a small impedance, there is a problem that a circuit size increases and a frequency response characteristic is limited.